Quarterly Tax Payments Self-Employed UK 2026 — The Complete Guide
If you earn money as a freelancer, contractor, or sole trader in the UK, HMRC expects you to pay tax in advance — four times per year, whether you've saved for it or not. This system, called payments on account, is the reason thousands of self-employed workers face a shock each January when a bill arrives that can exceed their entire December earnings.
This guide explains exactly how quarterly tax payments work, why they catch so many people off guard, and exactly what you need to do to avoid the twin traps of Year 2 double billing and penalty charges.
What Are Payments on Account?
Payments on account are advance payments towards your final tax bill for the year. They're HMRC's way of collecting tax from self-employed people who don't have an employer deducting it at source.
Here's how it works:
- Each year, when you complete your Self Assessment tax return (due by 31 January), HMRC calculates your tax for the previous tax year (which ran from 6 April to 5 April)
- They then estimate that you'll earn the same amount in the current tax year
- They divide that estimated tax by two — these are your payments on account
- You pay two equal instalments: one by 31 January, one by 31 July
Here's the catch: these payments are based on the previous year's income, not what you've actually earned this year. So if your income increased significantly, you're likely underpaying. If it dropped, you're likely overpaying.
The Double-Bill Trap (Year 2)
For brand-new self-employed workers in their second year, the first payment on account combines:
- Your balancing payment — the actual tax owed for Year 1
- Your first payment on account — an advance towards Year 2
That means January's bill is roughly double what you'd expect. This catches thousands of first-year freelancers every year. They completed their first return, thought they were done, and then received a second bill for £5,000+ that they have no idea how to pay.
Self Assessment Payment Dates for 2025/26
For the tax year 2025/26 (6 April 2025 to 5 April 2026), here are your key dates:
| Payment | Due Date | What It Covers |
|---|---|---|
| First payment on account | 31 July 2025 | 50% of estimated tax for 2025/26 |
| Balancing payment | 31 January 2026 | Final tax owed for 2024/25 |
| Second payment on account | 31 January 2026 | 50% of estimated tax for 2025/26 |
| Crystallising payment | 31 January 2027 | Final tax owed for 2025/26 |
Note: The 31 January and 31 July deadlines are hard deadlines. Late payments trigger automatic penalties.
How to Calculate Your Payments on Account
Let me walk you through the calculation with real numbers. This matters because understanding the math is the first step to planning ahead.
Step 1: Find Your Final Tax Bill
Complete your Self Assessment return. Your final tax bill is the sum of:
- Income tax (at 0%, 20%, 39.35% or 45% depending on earnings above Personal Allowance and Additional Rate thresholds)
- Class 4 National Insurance (9% on profits between £12,570 and £50,270, plus 2% on profits above £50,270)
- Any student loan repayments (Plan 1 or 2, 9% of earnings above the threshold)
Step 2: Divide by Two
Your payment on account is half of your total tax bill (income tax + Class 4 NIC).
Example: Sarah, a freelance designer in Year 1
Sarah earns £45,000 gross in her first year of self-employment.
- Personal Allowance: £12,570
- Taxable profit: £32,430
- Income tax: £6,486 (20% on £32,430)
- Class 4 NIC: £2,078 (£37,700 × 9%)
- Total tax bill: £8,564
Her payments on account for Year 2 will be:
- Each payment: £4,282 (£8,564 ÷ 2)
- Due 31 July 2025 + 31 January 2026
But that's not her only January bill. She also owes the balancing payment for Year 1:
- January 2026 total: £8,564 (£4,282 balancing + £4,282 first payment on account)
This is Sarah's first experience of the double bill. If she hadn't planned for it, she's now scrambling to find £8,500 in 12 weeks.
Established Freelancer Example
Example: Marcus, a freelance developer at £80,000/year
Marcus has been self-employed for four years. His 2024/25 tax bill was:
- Income tax: £19,478
- Class 4 NIC: £4,263
- Total: £23,741
His payments on account for 2025/26:
- Each payment: £11,870.50
- Due 31 July 2025 and 31 January 2026
- His final bill in January 2027 may be higher or lower depending on his actual 2025/26 earnings
For Marcus, these payments are routine. He sets aside roughly £1,000 per month in a dedicated savings account and treats the January/July deadlines like a recurring bill — because that's exactly what they are.
How to Reduce Your Payments on Account
If your income has dropped significantly, you can apply to reduce your payments on account. This is one of the most underused provisions in the self-assessment system, and it can literally save you thousands in cash flow.
When to Apply
You should consider reducing your payments on account if:
- You've switched jobs or reduced hours
- You've taken on permanent employment alongside freelance work
- Your client work has dried up
- You've retired or scaled back
- You suffered illness or other circumstances affecting work
How to Apply
- Log in to your HMRC Personal Tax Account
- Go to Self Assessment > Payment on Account
- Select "Reduce payments on account"
- Enter your estimated tax for the current year
- Submit the estimate
Important: HMRC doesn't check your estimate in detail. But if you end up earning significantly more than your estimate, you'll face interest charges on the shortfall. There's no penalty for underestimating in good faith — but there is interest.
Real Example: Income Drop
Example: Priya, a writer whose income dropped from £65K to £35K
Priya was earning £65K in 2023/24, so her payments on account for 2024/25 were set at:
- Each payment: ~£7,800
- Total annual: ~£15,600
But in mid-2024, a major client ended their contract. Her income dropped to £35K. She reduced her payments on account to reflect ~£40K estimated earnings:
- New each payment: ~£4,500
- Annual savings in cash flow: £11,100
This gave her breathing room while she rebuilt her client base. When she completed her 2024/25 return, she actually owed less tax than the reduced payments, so HMRC sent her a refund.
What Happens If You Miss a Payment
HMRC's penalty system is unforgiving. Here's what you're dealing with:
| Days Late | Penalty |
|---|---|
| 1 day late | 5% of unpaid tax, or £100 (whichever is higher) |
| 3 months late | Additional 5% of unpaid tax |
| 6 months late | Additional 5% of unpaid tax, plus 5% of unpaid tax on amount outstanding at 3 months |
| 12 months late | Additional 5% of unpaid tax, plus 5% of unpaid tax on amounts outstanding at 3 and 6 months |
In practice, missing a £5,000 payment by three months triggers:
- Initial penalty: £100 (or 5% = £250, whichever is higher)
- 3-month penalty: Additional £250
- Interest on the unpaid amount: currently 7.25% APR (HMRC's interest rate tracks Bank of England base rate)
Don't rely on payment plans. HMRC does offer Time to Pay arrangements, but these are intended for genuine financial hardship — not as a routine deferral option. Setting up a payment plan can also affect your credit rating if HMRC references it.
The Psychology of Saving for Tax — Why It's So Hard
Here's the uncomfortable truth: most self-employed people don't save enough for tax, and it's not because they're irresponsible. There's a genuine psychological phenomenon at play.
The Future Self Discount
Behavioural economists call it hyperbolic discounting — we value immediate rewards far more than future rewards. When you're looking at your bank account in March and your tax isn't due until January, it's easy to think "I'll save more later."
But "later" never arrives with more money. It arrives with the same expenses and the same income, just now with a deadline.
Most employees never face this. Their employer withholds tax before they ever see the money. But as a freelancer, you're handling your own levy — and your brain isn't wired to withhold money you've already earned.
The Income Volatility Problem
Freelance income isn't steady. You might earn £8,000 in January, £2,000 in February, and £12,000 in March. This makes it genuinely hard to know how much to set aside.
The solution isn't willpower — it's systems. Here's what works:
- Set a fixed percentage: Take 25-30% off every invoice immediately. Don't wait until end-of-year. If £3,000 lands in your account, move £750 to a separate account before you spend a penny.
- Use a business bank account: Services like Bankrolled allow you to separate your tax allocation automatically. Money that leaves your main account before you see it doesn't tempt you.
- Name your savings: Call it "tax money" not "savings." The specific destination makes it feel less available for spending.
The Shock of Year 2
The double-bill in Year 2 deserves special mention because it catches even prepared people off guard. You've just filed your first return, paid your first tax bill, and breathed a sigh of relief. Then January rolls around again with another massive bill.
Here's why this happens: in Year 1, you only owe tax on what you earned that year. There's no advance payments yet. But in Year 2, you owe two things at once:
- The balance of Year 1 tax (because your payments on account were based on a zero estimate)
- The first payment on account for Year 2
If you anticipated this and saved accordingly, you're fine. If you didn't, you're looking at a bill that's roughly 150-200% of your first-year payment.
Common Mistakes Self-Employed People Make
Mistake #1: Confusing Payments on Account with Final Tax
Your payments on account are estimates. They're based on last year's income, not this year's. When you complete your return in January 2027 for the 2025/26 tax year, your final bill may be higher or lower than the payments you've made.
If it's higher, you pay the difference. If it's lower, HMRC refunds the excess. Think of payments on account as instalments, not your final bill.
Mistake #2: Not Budgeting for the Year 2 Double Bill
If you're new to self-employment, budget for your January Year 2 payment to be roughly double what you paid in Year 1. The exact amount depends on your earnings, but £5,000-£10,000 is common for moderate earners.
The safe rule: in Year 1, save 50% more than your tax bill to prepare for Year 2's double impact.
Mistake #3: Not Claiming a Reduction When Income Falls
If your income drops, your payments on account may be too high. Don't just overpay and hope for a refund — claim a reduction. It improves your cash flow immediately.
This is especially important if you've moved from full-time employment to freelance, or if you've taken on a permanent role alongside freelance work. Your income profile has changed, and your tax payments should reflect that.
Mistake #4: Forgetting About Class 2 National Insurance
Most articles focus on income tax, but Class 2 National Insurance is part of your bill too. For 2025/26, Class 2 is payable on profits above £12,570 at a rate of 9%.
If you're near the threshold, factor this in. And if your profits are below £12,570, you may get National Insurance credits without paying — but you're not automatically exempt from filing.
Mistake #5: Using Tax Money for Business Expenses
It's incredibly tempting to treat your tax savings as working capital when cash is tight. But this is the fast track to a January crisis. If you've spent your tax money, you can't un-spend it.
Treat your tax savings as untouchable. Move them to a separate account you don't check regularly. Set up a standing order so it happens automatically the day after you get paid.
Tax Software for Self-Employed Workers
Managing quarterly tax payments is infinitely easier with the right tools. Here are the main options, evaluated for self-employed freelancers specifically:
| Software | Best For | Key Feature | Approximate Price |
|---|---|---|---|
| Earnr | Side hustlers and new freelancers | Automatic tax estimate on every invoice; designed specifically for UK self-employed | Free-£12/month |
| Xero | Growing freelance businesses | Real-time tax estimate dashboard; connects to bank feeds | £13-£24/month |
| Sage | Contractors with complex accounts | Comprehensive reporting; strong for VAT and payroll | £14-£32/month |
| FreeAgent | Freelancers wanting simplicity | Clean interface; built-in tax timeline reminders | £10-£15/month |
Why this matters: Good tax software doesn't just record your income — it estimates what you'll owe. This means you can set aside the right amount all year, rather than scrambling in January.
Earnr is particularly strong for this use case because it was built specifically for UK side hustlers and freelancers. It estimates your tax on every invoice, helping you visualise exactly what you need to reserve.
Key Takeaways
- Payments on account are advance tax payments based on last year's income — you pay twice yearly (31 January and 31 July)
- The Year 2 double bill catches most new freelancers off guard — budget 150-200% of your Year 1 payment
- You can reduce payments if your income has dropped — this is legal, encouraged, and improves cash flow
- Late payments trigger penalties — 5% after 1 day, escalating quickly
- Save proactively — set aside 25-30% of every payment, automatically, before you spend it
- Use tax software — tools like Earnr, Xero, or FreeAgent estimate your liability in real time
Quarterly tax payments aren't optional, and they don't disappear. But with the right system — automatic savings, realistic budgeting, and the occasional HMRC adjustment — they're manageable. The freelancers who thrive aren't those who earn the most. They're the ones who've built the best systems.
If you're new to freelancing and wondering about VAT registration, our complete guide to the freelancer VAT threshold covers everything you need to know about when and how to register.
For broader financial planning, see our first-time buyer's guide to understand the psychology of major financial decisions.
Start building yours today.
HMRC deadlines and thresholds in this guide reflect the 2025/26 tax year. Tax rates and thresholds may change in future years — always verify current rates at gov.uk or with a qualified accountant.